66195554 has 4 divisors (see below), whose sum is σ = 99293334. Its totient is φ = 33097776.

The previous prime is 66195529. The next prime is 66195557. The reversal of 66195554 is 45559166.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 65044225 + 1151329 = 8065^2 + 1073^2 .

It is not an unprimeable number, because it can be changed into a prime (66195557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16548887 + ... + 16548890.

Almost surely, 2^66195554 is an apocalyptic number.

66195554 is a deficient number, since it is larger than the sum of its proper divisors (33097780).

66195554 is a wasteful number, since it uses less digits than its factorization.

66195554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33097779.

The product of its digits is 162000, while the sum is 41.

The square root of 66195554 is about 8136.0650194059. The cubic root of 66195554 is about 404.5227401508.

The spelling of 66195554 in words is "sixty-six million, one hundred ninety-five thousand, five hundred fifty-four".